Patients with coronary artery disease and undergoing high-risk percutaneous coronary intervention (PCI) are at increased risk of hemodynamic instability and poor outcomes. Mechanical circulatory support (MCS) devices may offer hemodynamic stabilization during PCI, potentially improving short- and long-term outcomes. The study rationale is to investigate the safety and clinical efficacy of temporary MCS with the iVAC 2L transaortic device in high-risk percutaneous coronary intervention. The transaortic system for short-term circulatory support with pulsatile blood flow iVAC 2L consists of an external membrane pump, a 17Fr diameter catheter for reversed blood flow (intake cannula) with a patented two-way rotary valve. The pump has two chambers, one for blood and one for helium, separated by a flexible diaphragm. The blood chamber connects to the catheter and the air chamber connects to a standard IABP console. The bi-directional valve is located 72 mm from the aspiration tip of the catheter and determines the direction of blood flow. The catheter is advanced retrogradely through the common femoral artery so that the tip is located in the left ventricular (LV) cavity and the valve is in the ascending aorta. Synchronized with the cardiac cycle via ECG, the device draws blood from the LV into the pump chamber during systole and ejects blood from the pump into the ascending aorta during diastole. The primary composite outcome is all-cause mortality, including acute myocardial infarction, stroke and TIA during hospitalization and at Day 360 of follow-up, expressed as a percentage of total patients.